Christine Negroni riffs on aviation and travel and whatever else inspires her to put words to page.

Wednesday, March 13, 2013

787 Battery Box Has Boeing Confined

Battery from ANA Dreamliner. Photo courtesy JTSB

The materials engineers at Boeing are probably already calculating the size and shape of the new box that will confine the Dreamliner's lithium ion batteries. But it will take a magician to get Boeing out of the box it's presently in. It has an airplane tied up to its wingnuts with a battery technology that may have to go and every way it turns, it finds another corner it cannot navigate.

Lithium ion, you recall, was selected because of Boeing's desire to get a lighter, more fuel efficient airplane. By using two sixtyish pound batteries to provide some of the airplane's voracious power and backup power demands, the 787 saved the weight of a suitcase or two. The heavier issue, excuse the pun, is all the reductions that Boeing achieved by making the 787 an electric airplane. Ductwork, motors, compressors, valves, heat shields and more have been removed from the engines and the airframe.

What does not seem to be addressed by Boeing or the FAA, but of interest to the NTSB is a phenomenon called "field failure." You want to talk prickly? From the description taken from a report published by physicist Lewis Larsen, this is the mother of prickly problems.

A field failure is a random event that can occur right off the battery production line, Larsen writes. It is undetectable and unpreventable. But when one of these microscopically small failures gets going it becomes a miniature flash fireball generating temperatures that can peak as high as 5,000-10,000 degrees Fahrenheit.

Barnett writes about "violent flaming and extremely high temperatures". Oh yeah, he also mentions the possibility of explosive combustion.

"Most safety tests carried out in the laboratory or factory do not replicate the conditions by which safety incidents actually occur," Barnett writes. The consequences for Boeing and its nail-in-the-cell tests should be obvious. (Read my post on why the frequency of these events makes it impossible for Boeing to meet certification requirements, here.)

Round about now you may be asking why Boeing, when faced with this information didn't fly non-stop to an alternative energy source. Well, the selection of this battery chemistry was made 7 or 8 years ago, even before the spontaneous combustion of scads of laptops, cell phones and other electronic doo-dads forced the recall of millions of lithium ion batteries. By the time battery scientists were starting to nod their heads and stroke their chins in dismay, Boeing's sub contractor Thales had already convinced Boeing that this particular energy source was the way to go.

Given the time spent developing the Dreamliner's battery power system, it is understandable if Boeing isn't searching on Google for suppliers of a less troublesome battery. It would be like trying to replace gas furnace with a space heater by plugging it into the plumbing.

The question is, can Boeing find a safer way to use lithium ion? Or is it wasting time, money, energy and the last frazzled shred of its customers' good will when what it ought to be doing is beginning the long process of selecting and implementing an alternative? Very. Tough. Call. Most people I speak with share my sentiment that being Boeing is the worst thing you can be right now.

Boeing is about to start producing containment boxes for its upcoming FAA certification flights. Right away I recommend it place a classified ad in the Seattle Times and the ad should read like this:

HELP WANTED: Magicians needed immediately in Everette, Washington. Candidates with experience slipping out of heavy chains and operating in confined spaces will be given top consideration.